[PATCH 18/20] drm/i915/vrr: Use fixed timings for platforms that support VRR

[Ankit Nautiyal]

For fixed refresh rate use fixed timings for all platforms that support
VRR. For this add checks to avoid computing and reading VRR for
platforms that do not support VRR.
For platforms that do support VRR, readback vrr timings whether or not
VRR_CTL_FLIP_LINE_EN is set in VRR_CTL or not.

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
---
 drivers/gpu/drm/i915/display/intel_vrr.c | 43 ++++++++++++------------
 1 file changed, 22 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index 551dcc16f0d4..975fed9930c1 100644
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -344,6 +344,9 @@ intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
 	struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
 	int vmin = 0, vmax = 0;
 
+	if (!HAS_VRR(display))
+		return;
+
 	if (adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE)
 		return;
 
@@ -358,9 +361,6 @@ intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
 
 	vmin = intel_vrr_compute_vmin(crtc_state);
 
-	if (vmin >= vmax)
-		return;
-
 	crtc_state->vrr.vmin = vmin;
 	crtc_state->vrr.vmax = vmax;
 
@@ -373,7 +373,7 @@ intel_vrr_compute_config(struct intel_crtc_state *crtc_state,
 	 */
 	crtc_state->vrr.vmin -= intel_vrr_flipline_offset(display);
 
-	if (crtc_state->uapi.vrr_enabled)
+	if (crtc_state->uapi.vrr_enabled && vmin < vmax)
 		intel_vrr_compute_vrr_timings(crtc_state);
 	else if (is_cmrr_frac_required(crtc_state) && is_edp)
 		intel_vrr_compute_cmrr_timings(crtc_state);
@@ -640,6 +640,9 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 	u32 trans_vrr_ctl, trans_vrr_vsync;
 
+	if (!HAS_VRR(display))
+		return;
+
 	trans_vrr_ctl = intel_de_read(display,
 				      TRANS_VRR_CTL(display, cpu_transcoder));
 
@@ -663,23 +666,21 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
 			crtc_state->vrr.pipeline_full =
 				REG_FIELD_GET(VRR_CTL_PIPELINE_FULL_MASK, trans_vrr_ctl);
 
-	if (trans_vrr_ctl & VRR_CTL_FLIP_LINE_EN) {
-		crtc_state->vrr.flipline = intel_de_read(display,
-							 TRANS_VRR_FLIPLINE(display, cpu_transcoder)) + 1;
-		crtc_state->vrr.vmax = intel_de_read(display,
-						     TRANS_VRR_VMAX(display, cpu_transcoder)) + 1;
-		crtc_state->vrr.vmin = intel_de_read(display,
-						     TRANS_VRR_VMIN(display, cpu_transcoder)) + 1;
-
-		if (HAS_AS_SDP(display)) {
-			trans_vrr_vsync =
-				intel_de_read(display,
-					      TRANS_VRR_VSYNC(display, cpu_transcoder));
-			crtc_state->vrr.vsync_start =
-				REG_FIELD_GET(VRR_VSYNC_START_MASK, trans_vrr_vsync);
-			crtc_state->vrr.vsync_end =
-				REG_FIELD_GET(VRR_VSYNC_END_MASK, trans_vrr_vsync);
-		}
+	crtc_state->vrr.flipline = intel_de_read(display,
+						 TRANS_VRR_FLIPLINE(display, cpu_transcoder)) + 1;
+	crtc_state->vrr.vmax = intel_de_read(display,
+					     TRANS_VRR_VMAX(display, cpu_transcoder)) + 1;
+	crtc_state->vrr.vmin = intel_de_read(display,
+					     TRANS_VRR_VMIN(display, cpu_transcoder)) + 1;
+
+	if (HAS_AS_SDP(display)) {
+		trans_vrr_vsync =
+			intel_de_read(display,
+				      TRANS_VRR_VSYNC(display, cpu_transcoder));
+		crtc_state->vrr.vsync_start =
+			REG_FIELD_GET(VRR_VSYNC_START_MASK, trans_vrr_vsync);
+		crtc_state->vrr.vsync_end =
+			REG_FIELD_GET(VRR_VSYNC_END_MASK, trans_vrr_vsync);
 	}
 
 	crtc_state->vrr.enable = trans_vrr_ctl & VRR_CTL_VRR_ENABLE &&
-- 
2.45.2